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The eternal sexual question men from all walks of life ask is about size and whether it matters or not. While many men pride themselves on the size of their penis, believing an above-average size feeds the sexual appetite of their partner, is it really much more satisfying than its smaller counterpart? To settle one of life’s sexual mysteries head first, Mitchell Moffit and Gregory Brown of ASAPScience use studies, history, and human evolution to address the penis size debate.

“Interestingly, humans have the largest penis of any primate both in absolute size and relative body proportions," say the folks in the ASAPScience video “Does Penis Size Matter?” Evolutionary history explains why women most likely developed an interest in the preference for penis shape and size similar to the female peacock’s preference for males with stunning feathers. So where does penis length count?

The length of the penis plays a role when it comes to sperm and sexual intercourse. A longer penis is effective in removing the sperm rival males during sexual intercourse. The deeper the penis is in the vagina, the better it works with semen displacement, ensuring your genes get passed on. A 2012 study found some women experience more frequent vaginal orgasms with longer penises, suggesting it is able to stimulate the vagina and cervix.

However, a bigger penis isn’t always better. A 2013 study found when women were asked to rate the attractiveness of males based on computer-generated images of different body types and penis sizes, taller and fitter men were much more desirable, but a flaccid penis played a role in their perceived attractiveness. Female participants' attraction diminished when viewing flaccid penises larger than about 7.6 centimeters.

A penis in proportion with the male body is much more desirable. The person attached to the penis makes a difference, says ASAPScience. Confidence, an enjoyable personality, and attraction are strong predictors of sexual satisfaction, and weigh far higher than disproportionate penis size. The less-endowed can now rest assured — your personality will make up for it.